Most simple unidirectional remote-controlled systems using infrared or radio include one remote-controller that is paired with one remotely-controlled device. In some instances, there may be two or more identical remotely-controlled devices within range of that remote-controller's transmitter. In such cases, it may be necessary to prevent that transmitter from controlling a second device within its transmission range. This is a common problem in, for example, a house having multiple remote-controlled ceiling fans.
One solution to this problem includes setting a code on a dip switch on the device being controlled so that it matches a corresponding code that has been set on the remote-controller's transmitter. This permits operation of two remote-controllers for two different remotely-controlled devices without interference between them.
In some remote-controlled systems, this pairing is carried out by having a learning button on the device. In these cases, pressing the learning button initiates a sequence during which pairing can occur.
In many cases, it is useful to be able to control multiple identical remotely-controlled devices at once. For example, in lighting systems, it is useful to have the ability to dim or turn off selected groups of light-fixtures. In most cases, this is carried out by placing a group of light-fixtures to be controlled on the same electrical circuit and wiring that circuit to a dimmer circuit mounted on a nearby wall or panel. Any other groups of light-fixtures would be placed on additional circuits, each wired to a dedicated dimmer or switch.
This solution suffers from a lack of flexibility as well as difficulty in installation.
In principle, one could set dip switches on each of the light-fixtures involved. However, this is a laborious undertaking when many light-fixtures are involved. Moreover, the light-fixtures themselves may be mounted out of reach, thus making the task dangerous as well as laborious.